723 research outputs found

    Partial cricotracheal resection for pediatric subglottic stenosis: a single institution's experience in 60 cases

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    Abstract.: In our study, 60 infants and children, each with a severe subglottic stenosis (SGS), underwent partial cricotracheal resection (PCTR) with primary thyrotracheal anastomosis. According to the Myer-Cotton classification, two were grade II, 41 were grade III and 17 were grade IV stenoses. Of the 60 patients, 57 (95%) are presently decannulated, and one patient sustained a complete restenosis. Two patients with better than 80% subglottic airways still are waiting for decannulation: one because of bilateral cricoarytenoid joint fixation and the second because of temporary stenting of the subglottis with a Montgomery T-tube. The rate of decannulation is 97% (36 of 37 cases) in primary PCTRs, 100% (13 of 13 cases) in salvage PCTRs for failed laryngotracheal reconstructions (LTR) and 70% (7 of 10 cases) in extended PCTRs (i.e., PCTR associated with an additional open-airway procedure

    Definitive Evidence for Order-by-Quantum-Disorder in Er2Ti2O7

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    Here we establish the systematic existence of a U(1) degeneracy of all symmetry-allowed Hamiltonians quadratic in the spins on the pyrochlore lattice, at the mean-field level. By extracting the Hamiltonian of Er2Ti2O7 from inelastic neutron scattering measurements, we then show that the U(1)-degenerate states of Er2Ti2O7 are its classical ground states, and unambiguously show that quantum fluctuations break the degeneracy in a way which is confirmed by experiment. This is the first definitive observation of order-by-disorder in any material. We provide further verifiable consequences of this phenomenon, and several additional comparisons between theory and experiment.Comment: 4.5 pages, 3 figures, 7.5 pages of Supplemental Material, 8 supplemental figure

    Modélisation de l'évolution du couvert nival, sur le sous-bassin LG4 de la riviÚre La Grande dans le nord du Québec, à l'aide du modÚle français CROCUS

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    Au QuĂ©bec, l'accumulation de la neige au sol prend une grande importance dans bon nombre d'activitĂ©s humaines comme la production d'hydroĂ©lectricitĂ©. Face Ă  cette importance de la neige, il devient fort intĂ©ressant de faire appel Ă  des outils de modĂ©lisation dans le but de faire le suivi complet du manteau neigeux par la simulation des diffĂ©rents processus physiques agissant sur le couvert nival. En ce sens, la prĂ©sente recherche vise Ă  Ă©valuer la capacitĂ© d'adaptation aux conditions environnementales du QuĂ©bec, du modĂšle français multicouches CROCUS de suivi et de fonte du couvert nival, en vue de son utilisation ultĂ©rieure. Le choix du site d'Ă©tude s'accorde avec la prĂ©sence de stations d'acquisition de donnĂ©es sur le couvert nival et la disponibilitĂ© d'un large Ă©ventail de donnĂ©es mĂ©tĂ©orologiques essentielles aux modĂ©lisations.Suite au prĂ©traitement des donnĂ©es d'entrĂ©e, le modĂšle CROCUS a pu ĂȘtre Ă©talonnĂ© dans le but d'Ă©valuer ses aptitudes Ă  simuler l'Ă©volution de l'Ă©paisseur et de l'Ă©quivalent en eau du couvert nival, de mĂȘme que les profils de densitĂ© et de tempĂ©rature de ce couvert. Compte tenu des donnĂ©es disponibles, les rĂ©sultats des pĂ©riodes d'Ă©talonnage et de vĂ©rification peuvent ĂȘtre considĂ©rĂ©s comme trĂšs bons et trĂšs encourageants pour des applications ultĂ©rieures de CROCUS au QuĂ©bec.In QuĂ©bec, snow accumulation on the ground is important for a large number of activities, including hydroelectric production. Snow being an important environmental aspect to look at for operations in cold regions, making use of adequate models able to simulate the various physical processes affecting the characteristics of the snowpack throughout the entire snow season becomes also quite important. So, the present project aims to evaluate the ability of the CROCUS French multilayer snow model to be adapted to Northern Quebec environmental conditions. The choice of the study area has been done on the basis of data availability on both the temporal evolution the snowpack at three automatic stations and the meteorological variables necessary as input to the model. Following preprocessing of input data, the CROCUS model has been calibrated in order to evaluate his capability to simulate the temporal evolution not only of the thickness and water equivalent of the snowpack, but also of the density and temperature profiles within the pack. Given the available data, the results for both the calibration and verification periods can be considered as good and very encouraging for future applications of the CROCUS model in QuĂ©bec

    Simultaneous Determination of Human Plasma Levels of Citalopram, Paroxetine, Sertraline, and Their Metabolites by Gas Chromatography—Mass Spectrometry

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    A gas chromatography—mass spectrometry method is presented which allows the simultaneous determination of the plasma concentrations of the selective serotonin reuptake inhibitors citalopram, paroxetine, sertraline, and their pharmacologically active N-demethylated metabolites (desmethylcitalopram, didesmethylcitalopram, and desmethylsertraline) after derivatization with the reagent N-methyl-bis(trifluoroacetamide). No interferences from endogenous compounds are observed following the extraction of plasma samples from six different human subjects. The standard curves are linear over a working range of 10-500 ng/mL for citalopram, 10-300 ng/mL for desmethylcitalopram, 5-60 ng/mL for didesmethylcitalopram, 20-400 ng/mL for sertraline and desmethylsertraline, and 10-200 ng/mL for paroxetine. Recoveries measured at three concentrations range from 81 to 118% for the tertiary amines (citalopram and the internal standard methylmaprotiline), 73 to 95% for the secondary amines (desmethylcitalopram, paroxetine and sertraline), and 39 to 66% for the primary amines (didesmethylcitalopram and desmethylsertraline). Intra- and interday coefficients of variation determined at three concentrations range from 3 to 11 % for citalopram and its metabolites, 4 to 15% for paroxetine, and 5 to 13% for sertraline and desmethylsertraline. The limits of quantitation of the method are 2 ng/mL for citalopram and paroxetine, 1 ng/mL for sertraline, and 0.5 ng/mL for desmethylcitalopram, didesmethylcitalopram, and desmethylsertraline. No interferences are noted from 20 other psychotropic drugs. This sensitive and specific method can be used for single-dose pharmacokinetics. It is also useful for therapeutic drug monitoring of these three drugs and could possibly be adapted for the quantitation of the two other selective serotonin reuptake inhibitors on the market, namely fluoxetine and fluvoxamin

    People making deontological judgments in the Trapdoor dilemma are perceived to be more prosocial in economic games than they actually are

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    Why do people make deontological decisions, although they often lead to overall unfavorable outcomes? One account is receiving considerable attention: deontological judgments may signal commitment to prosociality and thus may increase people’s chances of being selected as social partners–which carries obvious long-term benefits. Here we test this framework by experimentally exploring whether people making deontological judgments are expected to be more prosocial than those making consequentialist judgments and whether they are actually so. In line with previous studies, we identified deontological choices using the Trapdoor dilemma. Using economic games, we take two measures of general prosociality towards strangers: trustworthiness and altruism. Our results procure converging evidence for a perception gap according to which Trapdoor-deontologists are believed to be more trustworthy and more altruistic towards strangers than Trapdoor-consequentialists, but actually they are not so. These results show that deontological judgments are not universal, reliable signals of prosociality

    Diseases of groundnut in West Africa and their management: Research priorities and strategies

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    Diseases are major constraints to groundnut production in West Africa. Leaf spots, rust, rosette and seedling diseases are present throughout most of the region and cause substantial losses in yield. Crop growth variability is a major yield‐limiting factor in the Sahel. Aflatoxin contamination is a serious quality problem in the region. Strategies for management of these major diseases are briefly discussed with particular emphasis on the utilization of genetic resistanc

    Aboundance, diversity and distribution of ichthyoplanktons in creeks and coastal waters of Khouzestan Province

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    This study was carried out on Iranian coastal waters of Khouzestan province during 1995-98. Ichthyoplankton sampling was performed in order to determine its abundance, distribution and diversity. Monthly sampling was carried out from 12 fixed stations in Mahshar-Abadan creeks and 4 stations in west coasts of Khouzestan province waters, by a paired 500 micron Bongo net in oblique hauls from the bottom to the surface. Larvae of 21 families were identified in coastal waters. 16 families of fish larvae were also found in creeks. Most frequent larval families in the creeks were found to be Gobiidae (86%), Engraulidae (9.13%), Clupeidae (2.5%), and in west coasts, they were Gobiidae (49%), Engraulidae (14.5%) and Sciaenidae (7.8%). Other families were found to have a lower frequency and occured only in limited samples. There were distinct differences in fish families occured in two studied areas, although no significant differences were found in diversity of fish families there. The highest frequency of the larvae among most of the families was in March-August period. In the west coastal area, more than 50% of the total identified larvae occured in May, while in creeks, it was in April and June. Presence of larvae from different families showed significant differences. Grouping based on diversity and distribution by one way ANOVA showed the presence of two major spawning seasons in spring and autumn, plus two minor ones in summer and winter. Most of identified specimens were exclusive to neritic and intertidal zones, which live in soft clay substrate

    Efficiency of the traditional practice of traps to stimulate black truffle production, and its ecological mechanisms

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    The black truffle Tuber melanosporum was disseminated all over the world, propelled by the development of a wide variety of empirical practices. A widespread practice, called ‘truffle trap’, consists of placing pieces of truffles into excavations dug under host trees, and of collecting truffle in these traps in the next years. This research aims at (1) evaluating the effect of this practice on fruitbody production based on the analysis of 9924 truffle traps installed in 11 orchards across T. melanosporum native area in France and (2) exploring the mechanisms involved in fruitbody emergence using traps where the genotypes of introduced truffles were compared with those of fruitbodies collected in the same traps. We confirmed that truffle traps provide a major and highly variable part of truffle ground production, representing up to 89% of the collected fruitbodies. We evidenced a genetic link between introduced spores and collected fruitbodies, and then demonstrated that truffle growers provide paternal partners for mating with local maternal mycelia. We also highlighted that soil disturbance stimulate the vegetative development of established maternal mycelia. This research supports that a widely used traditional practice enhances fruitbody production by shaping favorable conditions and providing sexual partners required for fruiting.info:eu-repo/semantics/publishedVersio
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